<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .tri {
            width: 0;
            height: 0;
            margin: 0 auto;
            border-color: transparent pink transparent transparent;
            border-width: 200px 100px 0 0;
            border-style: solid;
        }
    </style>
</head>
<body>
    <div class="tri">

    </div>
</body>
</html>